Think about it. Russian suitcase nukes, Hole in the ozone, Avian flu, West nile, In the late 70’s, new ice age, then global warming, then Climate change, Swine flu, Aids, EMP, Mega quakes, rising ocean levels, acid rain...you name it.
When one hysteria ends, another begins almost immediately. I think it is a way to distract citizens....keep’em off kilter.
As long as you’re paying attention to the crisis you aren’t paying attention to their shenanigans.